For each compound, would you expect greater solubility in water or in hexane? Indicate the kinds of intermolecular forces that would occur between the solute and the solvent in which the molecule is most soluble. d. ethylene glycol

Key Concepts

Polarity of Molecules

Polarity refers to the distribution of electrical charge over the atoms in a molecule. Polar molecules, which have a significant difference in electronegativity between their atoms, tend to dissolve well in polar solvents like water. In contrast, nonpolar molecules, which have an even distribution of charge, are more soluble in nonpolar solvents like hexane.

Intermolecular Forces

Intermolecular forces are the forces of attraction or repulsion between neighboring particles (atoms, molecules, or ions). The main types include hydrogen bonding, dipole-dipole interactions, and London dispersion forces. The strength and type of these forces influence a compound's solubility in a given solvent, as similar types of intermolecular forces between solute and solvent enhance solubility.

Hydrogen Bonding

Hydrogen bonding is a strong type of dipole-dipole interaction that occurs when hydrogen is bonded to highly electronegative atoms like oxygen, nitrogen, or fluorine. Ethylene glycol, which contains hydroxyl (-OH) groups, can form hydrogen bonds with water, significantly increasing its solubility in polar solvents. This interaction is crucial for understanding why certain compounds dissolve better in water than in nonpolar solvents.